The present invention relates to inks comprising certain copper complex azo dyes based on 1-naphthol-3,6,8-trisulfonic acid or 1-naphthol-3,8-disulfonic acid as coupling component and to dye mixtures comprising the said dyes. The present invention relates also to the novel copper complex azo dyes contained in the inks or dye mixtures according to the invention.
The inks underlying the present invention are especially suitable for the printing of paper, textile fibre materials, plastics films or aluminium foils, especially using the ink-jet printing method, and yield magenta dyeings and prints having good fastness to light and a high colour brilliance.
The dyes and dye mixtures underlying the present invention are suitable for the preparation of the inks according to the invention and for the dyeing of paper, wood, textile fibre materials and aluminium sheets or foils using traditional dyeing and printing methods and yield magenta dyeings and prints having good fastness to light and a high colour brilliance.
Inks are subject to high demands in terms of their fastness to light and their colour brilliance. The known magenta inks do not fulfil all of those demands at the same time. For example, although the known inks produce recordings having good fastness to light, the colour shades in such cases are dull and have a low degree of brilliance, as, for example, in the case of inks that contain C.I. Reactive Red 23. On the other hand, other known inks yield recordings having a high degree of brilliance but do not provide the desired quality in terms of the fastness to light of the recordings.
The present invention is therefore based on the problem of providing improved inks for the dyeing and printing of paper, textile fibre materials, plastics films or aluminium foils that possess the qualities described above to a high degree. The new inks should produce brilliant colour shades and at the same time be distinguished by good fastness to light.
It has now been found, surprisingly, that inks comprising a copper complex structurally similar to C.I. Reactive Red 23 produce a brilliant, bluish magenta having good fastness to light.
The present invention accordingly relates to inks comprising a dye of formula (1) 
wherein
X is hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl, vinyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z is a group removable under alkaline conditions or is C1-C24alkoxy unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen; phenoxy unsubstituted or substituted in the phenyl ring; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety; phenylthio unsubstituted or substituted in the phenyl ring; amino; N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C10-C20terpeneamino; C5-C7cycloalkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom;
or X has the same definitions as Z with the exception of a group removable under alkaline conditions;
R is C1-C4alkyl, C1-C4alkoxy or halogen; and
m and n are each independently of the other the number 0, 1 or 2; and
an organic solvent.
Z as C1-C24alkoxy, especially C1-C12alkoxy and more especially C1-C4alkoxy is straight-chain or branched and is, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, sec-butoxy, isobutoxy or tert-butoxy. The mentioned radicals are unsubstituted or substituted in the alkyl moiety, for example by C1-C4alkoxy, e.g. methoxy or ethoxy; hydroxy; sulfo; sulfato or by carboxy. Radicals interrupted in the alkyl moiety by oxygen and unsubstituted or further substituted in the alkyl moiety are, for example, polyalkylene oxides having from 4 to 24 carbon atoms, for example polyethylene oxide of formula xe2x80x94(Oxe2x80x94CH2xe2x80x94CH2)2-12xe2x80x94OH, polypropylene oxide of formula 
and mixed polyethylene oxide/polypropylene oxide. The hydroxy group of the mentioned polyalkylene oxide radicals may have been etherified, for example by C1-C4alkyl, e.g. methyl or ethyl.
Z as C1-C4alkylthio is, for example, methylthio, ethylthio, propylthio, isopropylthio or n-butyl-thio. The mentioned radicals are unsubstituted or substituted in the alkyl moiety, for example by C1-C4alkoxy, e.g. methoxy or ethoxy; hydroxy; sulfo or by carboxy. Preference is given to the radicals substituted by one or two radicals from the group hydroxy, sulfo and carboxy.
Z as phenoxy or phenylthio can include both the unsubstituted radicals and the radicals substituted in the phenyl ring, for example by C1-C4alkyl, e.g. methyl or ethyl, which is unsubstituted or further substituted, e.g. by carboxy; C1-C4alkoxy, e.g. methoxy or ethoxy; carboxy; C2-C4alkanoylamino, e.g. acetylamino or propionylamino; carbamoyl; Nxe2x80x94C1-C4alkyl-carbamoyl, which is unsubstituted or further substituted in the alkyl moiety, e.g. by carboxy, for example N-carboxymethylcarbamoyl; sulfamoyl; Nxe2x80x94C1-C4alkylsulfamoyl; sulfo or by halogen, e.g. chlorine or bromine. Preference is given to the substituted radicals, especially the radicals substituted by carboxy, carboxymethyl, N-carboxymethylcarbamoyl or by sulfo, more especially those substituted by carboxy or sulfo.
Z as N-mono- or N,N-di-C1-C24alkylamino is, for example, methylamino, ethylamino, N,N-di-methylamino, N,N-diethylamino, isopropylamino, n-butylamino, sec-butylamino, isobutylamino or tert-butylamino, linear or branched pentylamino, hexylamino, heptylamino, octylamino, nonylamino, decylamino, undecylamino, dodecylamino, tridecylamino or tetradecylamino. The mentioned radicals are unsubstituted or substituted in the alkyl moiety, e.g. by phenyl (which may itself be substituted by carboxy, carbamoyl, sulfo or by sulfamoyl); amino; C2-C4alkanoylamino, e.g. acetylamino or propionylamino; C1-C4alkoxy, e.g. methoxy or ethoxy; hydroxy; sulfo; sulfato; carboxy; carbamoyl or by sulfamoyl. The mentioned radicals are uninterrupted or interrupted in the alkyl moiety by oxygen or by xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or C1-C4alkyl, e.g. methyl or ethyl, unsubstituted or substituted, for example by amino or by hydroxy, but is preferably hydrogen.
Examples of radicals that are substituted in the alkyl moiety and/or are interrupted in the alkyl moiety by oxygen or by xe2x80x94NR1xe2x80x94 include
N-xcex2-aminoethylamino, N-xcex2-aminopropylamino, N-xcex2-hydroxyethylamino, N,N-di-xcex2-hydroxyethylamino, N-2-(xcex2-hydroxyethoxy)ethylamino, N-2-[2-(xcex2-hydroxyethoxy)ethoxy]-ethylamino, N-2-(xcex2-hydroxyethylamino)ethylamino, N-2-(xcex2-aminoethylamino)ethylamino, polyethylene imines of formula xe2x80x94(NHxe2x80x94CH2xe2x80x94CH2)3xe2x80x94NH2 or xe2x80x94(NHxe2x80x94CH2xe2x80x94CH2)4xe2x80x94NH2, 
N-xcex2-sulfatoethylamino, N-xcex2-sulfoethylamino, N-carboxymethylamino, N-xcex2-carboxyethylamino, N-xcex1,xcex2-dicarboxyethylamino, N-xcex1,xcex3-di-carboxypropylamino, N-ethyl-N-xcex2-hydroxyethylamino and N-methyl-N-xcex2-hydroxyethylamino. Suitable unsubstituted and uninterrupted radicals that are branched in the alkyl moiety correspond, for example, to the formula 
wherein the sum of the carbon atoms Ra+Rb+Rc is from 11 to 14. An example of an amine forming the basis of the radical of the formula given above is (copyright)Primene 81 R (Rohm and Haas).
Z as N-mono- or N,N-di-C1-C24alkylamino that is substituted in the alkyl moiety and/or is interrupted in the alkyl moiety by oxygen or by xe2x80x94NR1xe2x80x94 in which R1 has the definitions and preferred meanings given above is preferably N-mono- or N,N-di-C1-C6alkylamino and especially N-mono- or N,N-di-C1-C4alkylamino.
Preferred for Z as N-mono- or N,N-di-C1-C24alkylamino are the radicals substituted in the alkyl moiety by phenyl, amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, especially by phenyl, amino, sulfo, sulfato, carboxy or by carbamoyl, and uninterrupted or interrupted in the alkyl moiety by xe2x80x94NHxe2x80x94.
Z as C10-C20terpeneamino, preferably C20diterpeneamino, is an amino group mono-substituted at the nitrogen atom by a terpene hydrocarbon radical. Examples of terpene hydrocarbon radicals that come into consideration are acyclic, monocyclic or bicyclic C10terpenes, acyclic, monocyclic, bicyclic or tricyclic C15sesquiterpenes, acyclic, monocyclic or tricyclic C20diterpenes, especially tricyclic C20diterpenes and more especially dehydrogenated tricyclic C20diterpenes, such as those derived from dehydroabietic acid. An example of such a dehydrogenated tricyclic C20diterpeneamino radical that may be mentioned is the radical of formula 
Z as C5-C7cycloalkylamino can include both the unsubstituted radicals and the radicals substituted in the cycloalkyl ring, for example by C1-C4alkyl, e.g. methyl or ethyl, especially methyl, or by carboxy. Such radicals are preferably the corresponding cyclohexyl radicals.
Z as phenylamino or Nxe2x80x94C1-C4alkyl-N-phenylamino, preferably phenylamino, can include both the unsubstituted radicals and the radicals substituted in the phenyl ring, for example by C1-C4alkyl, e.g. methyl or ethyl, which is unsubstituted or further substituted, e.g. by carboxy; C1-C4alkoxy, e.g. methoxy or ethoxy; carboxy; carbamoyl; Nxe2x80x94C1-C4alkylcarbamoyl, which is unsubstituted or further substituted in the alkyl moiety, e.g. by carboxy, for example N-carboxymethylcarbamoyl; sulfo or by halogen, e.g. chlorine or bromine. Preference is given to the substituted radicals, especially the radicals substituted by carboxy, carboxymethyl, N-carboxymethylcarbamoyl or by sulfo, more especially those substituted by sulfo.
Z as naphthylamino or Nxe2x80x94C1-C4alkyl-N-naphthylamino, preferably naphthylamino, can include both the unsubstituted radicals and the radicals substituted in the naphthyl ring, for example by sulfo. Preference is given to the radicals substituted by from 1 to 3, especially 2 or 3, sulfo groups.
Z as piperazin-1-yl unsubstituted or substituted at the nitrogen atom is, for example, a radical of formula 
wherein
B is an organic bridge member and
Rxe2x80x2 is hydrogen or unsubstituted or substituted C1-C4alkyl,
W is hydrogen or a radical of formula xe2x80x94COxe2x80x94Rxe2x80x3, Rxe2x80x3 being unsubstituted or substituted C1-C8alkyl, C5-C7cycloalkyl, phenyl or naphthyl.
Examples of organic bridge members that come into consideration for B are, for example, unsubstituted or substituted C1-C12alkylene, which may be interrupted by 1, 2 or 3 members from the group xe2x80x94NHxe2x80x94, xe2x80x94N(CH3)xe2x80x94 and xe2x80x94Oxe2x80x94, and unsubstituted or substituted C5-C7cycloalkylene, phenylene or naphthylene. There comes into consideration as C5-C7cycloalkylene especially cyclohexylene which may be unsubstituted or substituted, for example by C1-C4alkyl, especially by methyl. Examples of substituents that come into consideration for the mentioned phenylene and napthylene radicals are C1-C4alkyl, C1-C4alkoxy, C2-C4alkanoylamino, amino, hydroxy, ureido, halogen, carboxy and sulfo, especially C1-C4alkyl, C1-C4alkoxy, halogen and sulfo. Examples of substituents that come into consideration for the mentioned C1-C12-alkylene radicals are hydroxy, sulfo, sulfato, cyano and carboxy. The C1-C12alkylene radicals are preferably unsubstituted.
For Rxe2x80x2 as C1-C4alkyl there come into consideration, for example, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl and isobutyl. The mentioned alkyl radicals may be unsubstituted or substituted, for example by hydroxy, sulfo, sulfato, cyano or by carboxy. Preferred as alkyl radicals are the corresponding unsubstituted radicals.
For Rxe2x80x3 as phenyl or naphthyl there come into consideration, in addition to the corresponding unsubstituted radicals, the radicals substituted, for example, by C1-C4alkyl, C1-C4alkoxy, C2-C4alkanoylamino, amino, hydroxy, ureido, halogen, carboxy or by sulfo.
For Rxe2x80x3 as C5-C7cycloalkyl there comes into consideration especially the cyclohexyl radical. The mentioned cycloalkyl radicals may be unsubstituted or substituted, for example by C1-C4alkyl, especially by methyl.
For Rxe2x80x3 as C1-C8alkyl there come into consideration especially C1-C4alkyl radicals, e.g. methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl or isobutyl. The alkyl radicals mentioned for Rxe2x80x3 may be unsubstituted or substituted, for example by hydroxy, sulfo, sulfato, cyano or by carboxy. Preferred for Rxe2x80x3 are the unsubstituted radicals.
B is preferably a C1-C12alkylene radical, especially a C1-C10alkylene radical, which may be interrupted by 1, 2 or 3 members from the group xe2x80x94NHxe2x80x94, xe2x80x94N(CH3)xe2x80x94 and especially xe2x80x94Oxe2x80x94 and which is unsubstituted or substituted by hydroxy, sulfo, sulfato, cyano or by carboxy. The corresponding unsubstituted alkylene radicals are of special interest.
B is especially a C1-C10alkylene radical, more especially a C1-C6alkylene radical and preferably a C1-C4alkylene radical. Radicals B that are of special interest are those of formulae xe2x80x94CH2xe2x80x94, xe2x80x94CH2CH2xe2x80x94 and xe2x80x94CH2CH2CH2xe2x80x94.
Rxe2x80x2 is preferably hydrogen or C1-C4alkyl unsubstituted or substituted by hydroxy, sulfo, sulfato, cyano or by carboxy, preferably hydrogen or C1-C4alkyl and especially hydrogen.
Rxe2x80x3 is preferably unsubstituted or C1-C4alkyl-, C1-C4alkoxy- , halo- , carboxy- or sulfo-substituted phenyl or especially C1-C8alkyl. Rxe2x80x3 is especially C1-C4alkyl, more especially methyl or ethyl and preferably methyl.
W is preferably hydrogen.
There come into consideration as C1-C4alkyl for X and R independently of one another, for example, methyl, ethyl, n- or iso-propyl and n-butyl, sec-butyl, tert-butyl and isobutyl, especially methyl and ethyl.
X as C1-C4alkyl is unsubstituted or substituted by hydroxy and is preferably unsubstituted.
For R as C1-C4alkoxy there come into consideration, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy and isobutoxy, preferably methoxy and ethoxy and especially methoxy.
R as halogen is, for example, fluorine, chlorine or bromine, preferably chlorine or bromine and especially chlorine.
As a group Z removable under alkaline conditions there comes into consideration, for example, xe2x80x94Cl, xe2x80x94Br, xe2x80x94F, xe2x80x94OSO3H, xe2x80x94SSO3H, xe2x80x94OCOxe2x80x94CH3, xe2x80x94OPO3H2, xe2x80x94OCOxe2x80x94C6H5, xe2x80x94OSO2-C1xe2x80x94C4alkyl or xe2x80x94OSO2xe2x80x94N(C1-C4alkyl)2. Z is preferably a group of formula xe2x80x94Cl, xe2x80x94OSO3H, xe2x80x94SSO3H, xe2x80x94OCOxe2x80x94CH3, xe2x80x94OCOxe2x80x94C6H5 or xe2x80x94OPO3H2, especially xe2x80x94Cl or xe2x80x94OSO3H and more especially xe2x80x94OSO3H.
Preference is given to the inks according to the invention wherein
R is C1-C4alkyl or halogen.
Preference is given to the inks according to the invention wherein
Z is xe2x80x94OSO3H; xe2x80x94Cl; C1-C12alkoxy unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy, which may further be interrupted in the alkyl moiety by one, two or three oxygen atoms; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; amino; N-mono- or N,N-di-C1-C14alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy, carbamoyl, sulfo or by sulfamoyl), amino, C2-C4alkanoylamino, hydroxy, sulfo, sulfato, carboxy, carbamoyl or by sulfamoyl, which may further be interrupted in the alkyl moiety by one, two or three oxygen atoms or xe2x80x94NR1xe2x80x94 groups in which R1 is hydrogen or unsubstituted or amino-substituted C1-C4alkyl; C20diterpeneamino; C5-C7-cycloalkylamino unsubstituted or substituted by C1-C4alkyl or by carboxy; phenylamino or Nxe2x80x94C1-C4alkyl-N-phenylamino unsubstituted or substituted by carboxymethyl, C1-C4alkoxy, carboxy, carbamoyl, Nxe2x80x94C1-C4alkylcarbamoyl (which may itself be further substituted in the alkyl moiety by carboxy), sulfo or by halogen; naphthylamino substituted in the aryl moiety by sulfo; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl or 3-aminopropyl.
Special preference is given to the inks according to the invention wherein
Z is xe2x80x94OSO3H; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; amino; N-mono- or N,N-di-C1-C14alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy, carbamoyl, sulfo or by sulfamoyl), amino, C2-C4alkanoylamino, hydroxy, sulfo, sulfato, carboxy, carbamoyl or by sulfamoyl, which may further be interrupted in the alkyl moiety by one, two or three oxygen atoms or xe2x80x94NHxe2x80x94 groups; C20diterpeneamino; phenylamino or Nxe2x80x94C1-C4alkyl-N-phenylamino unsubstituted or substituted by carboxymethyl, C1-C4alkoxy, carboxy, carbamoyl, Nxe2x80x94C1-C4alkylcarbamoyl (which may itself be further substituted in the alkyl moiety by carboxy), sulfo or by halogen; naphthylamino substituted in the aryl moiety by sulfo; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl.
Very special preference is given to the inks according to the invention wherein
Z is xe2x80x94OSO3H; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; amino; N-mono-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, which may further be interrupted in the alkyl moiety by one or two oxygen atoms or xe2x80x94NHxe2x80x94 groups; N,N-di-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl.
In an especially important embodiment of the inks according to the invention Z is xe2x80x94OSO3H; amino; N-mono-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, which may further be interrupted in the alkyl moiety by one or two oxygen atoms or xe2x80x94NHxe2x80x94 groups; N,N-di-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl.
X is hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl, vinyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z has the definitions and preferred meanings given above, or X has the same definitions as given above for Z with the exception of Z in the meaning of a group removable under alkaline conditions.
X is preferably hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl, vinyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z has the definitions and preferred meanings given above, or X is preferably amino; N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C5-C7cyclo-alkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom; the definitions and preferred meanings given above for Z also applying in corresponding manner to X.
X is especially hydroxy, C1-C4alkyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z has the definitions and preferred meanings given above, or X is especially amino; N-mono-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, which may further be interrupted in the alkyl moiety by one or two oxygen atoms or xe2x80x94NHxe2x80x94 groups; N,N-di-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl.
X is more especially hydroxy or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z is xe2x80x94OSO3H; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; amino; N-mono-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, which may further be interrupted in the alkyl moiety by one or two oxygen atoms or xe2x80x94NHxe2x80x94 groups; N,N-di-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl; or X is very especially amino; N-mono-C1-C4alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), hydroxy, sulfo, sulfato or by carboxy; N,N-di-C1-C4alkylamino unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl.
Especially important meanings of X are hydroxy, amino, methylamino, ethylamino and xe2x80x94CH2xe2x80x94CH2xe2x80x94OSO3H; and especially the radical xe2x80x94CH2xe2x80x94CH2xe2x80x94OSO3H.
In a preferred embodiment of the inks according to the invention
m is the number 0 or 1, especially 0, and
n is the number 1 or 2, especially 1.
Preference is given to the inks according to the invention wherein X is hydroxy or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z is xe2x80x94OSO3H; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; amino; N-mono-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl, which may further be interrupted in the alkyl moiety by one or two oxygen atoms or xe2x80x94NHxe2x80x94 groups; N,N-di-C1-C6alkylamino unsubstituted or substituted in the alkyl moiety by amino, hydroxy, sulfo, sulfato, carboxy or by carbamoyl; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl; or
X is amino; N-mono-C1-C4alkylamino unsubstituted or substituted in the alkyl moiety by phenyl (which may itself be substituted by carboxy), hydroxy, sulfo, sulfato or by carboxy; N,N-di-C1-C4alkylamino unsubstituted or substituted in the alkyl moiety by hydroxy, sulfo or by carboxy; morpholino; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom by 2-aminoethyl;
R is C1-C4alkyl or halogen;
m is the number 0 or 1 are
n is the number 1 or 2.
Special preference is given to the inks according to the invention wherein the dye of formula (1) is a dye of formula (2) 
The dyes used in the inks should preferably have a low salt content, that is to say they should have a total content of salts of less than 0.5% by weight, based on the weight of the dyes. Dyes that have relatively high salt contents as a result of their preparation and/or as a result of the subsequent addition of diluents can be desalted, for example, by membrane separation procedures, such as ultrafiltration, reverse osmosis or dialysis. The inks preferably have a total content of dyes of from 0.5 to 35% by weight, especially from 1 to 30% by weight and preferably from 1 to 20% by weight, based on the total weight of the ink. As a lower limit, a limit of 1.5% by weight, preferably 2% by weight and especially 3% by weight, is preferred.
The inks may comprise organic solvents, for example water-miscible organic solvents, e.g. C1-C4alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol and isobutanol; amides, e.g. dimethylformamide and dimethylacetamide, ketones or ketone alcohols, e.g. acetone, methyl isobutyl ketone, diacetone alcohol; ethers, e.g. tetrahydrofuran and dioxane; nitrogen-containing heterocyclic compounds, e.g. N-methyl-2-pyrrolidone and 1,3-dimethyl-2-imidazolidone; polyalkylene glycols, e.g. polyethylene glycol or polypropylene glycol; C2-C6alkylene glycols and thioglycols, e.g. ethylene glycol, propylene glycol, butylene glycol, 1,5-pentanediol, thiodiglycol, hexylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol and diethylene glycol monobutyl ether; further polyols, e.g. glycerol, and 1,2,6-hexanetriol; and C1-C4alkyl ethers of polyhydric alcohols, e.g. 2-methoxyethanol, 1-methoxypropanol, 2-(2-methoxyethoxy)ethanol, 2-(2-ethoxyethoxy)-ethanol, 2-[2-(2-methoxyethoxy)ethoxy]-ethanol and 2-[2-(2-ethoxyethoxy)-ethoxy]ethanol; preferably N-methyl-2-pyrrolidone, diethylene glycol, glycerol or especially 1,2-propylene glycol, usually in an amount of from 2 to 30% by weight, especially from 5 to 30% by weight and preferably from 10 to 25% by weight, based on the total weight of the ink.
The inks may also comprise solubilisers, e.g. xcex5-caprolactam.
The inks may comprise thickeners of natural or synthetic origin inter alia for the purpose of adjusting the viscosity.
Examples of thickeners that may be mentioned are commercially available alginate thickeners, starch ethers or locust bean flour ethers, especially sodium alginate on its own or in admixture with modified cellulose, e.g. methylcellulose, ethylcellulose, carboxymethycellulose, hydroxyethylcellulose, methylhydroxyethylcellulose, hydroxypropyl cellulose or hydroxypropyl methylcellulose, especially with preferably from 20 to 25% by weight carboxymethylcellulose. Synthetic thickeners that may be mentioned are, for example, those based on poly(meth)acrylic acids or poly(meth)acrylamides.
The inks comprise such thickeners, for example, in an amount of from 0.01 to 2% by weight, especially from 0.01 to 1% by weight and preferably from 0.01 to 0.5% by weight, based on the total weight of the ink.
The inks may also comprise buffer substances, e.g. borax, borates, phosphates, polyphosphates or citrates. Examples that may be mentioned include borax, sodium borate, sodium tetraborate, sodium dihydrogen phosphate, disodium hydrogen phosphate, sodium tripolyphosphate, sodium pentapolyphosphate and sodium citrate. They are used especially in amounts of from 0.1 to 3% by weight, preferably from 0.1 to 1% by weight, based on the total weight of the ink, in order to establish a pH value of, for example, from 4 to 9, especially from 5 to 8.5.
As further additives, the inks may comprise surfactants or humectants.
Suitable surfactants include commercially available anionic or non-ionic surfactants. As humectants in the inks according to the invention there come into consideration, for example, urea or a mixture of sodium lactate (advantageously in the form of a 50% to 60% aqueous solution) and glycerol and/or propylene glycol in amounts of preferably from 0.1 to 30% by weight, especially from 2 to 30% by weight.
Preference is given to inks having a viscosity of from 1 to 40 mPaxc2x7s, especially from 1 to 20 mPaxc2x7s and preferably from 1 to 10 mPaxc2x7s.
The inks may also comprise customary additives, such as antifoam agents or especially substances that inhibit the growth of fungi and/or bacteria. Such additives are usually used in amounts of from 0.01 to 1% by weight, based on the total weight of the ink.
The inks can be prepared in customary manner by mixing the individual constituents together, for example in the desired amount of water.
The inks according to the invention are especially suitable for use in recording systems of the type in which an ink is expressed in the form of droplets from a small aperture, the droplets being directed onto a substrate on which an image is produced. Suitable substrates are, for example, textile fibre materials, paper, plastics or aluminium foils. Suitable recording systems are, for example, commercially available ink-jet printers for use in paper or textile printing, or writing implements, such as fountain pens or ballpoint pens, especially ink-jet printers.
Depending upon the nature of the use it may be necessary, for example, to adjust the viscosity or other physical properties of the ink, especially those properties which have an effect upon the affinity for the substrate in question. For printing textile fibre materials, paper or plastics films it is preferable to use aqueous inks.
Examples of paper that can be printed using the inks according to the invention include commercially available ink-jet paper, photographic paper, glossy paper and plastics-coated paper, e.g. Epson ink-jet paper, Epson photo paper, Epson glossy paper, Epson glossy film, HP special ink-jet paper, Encad photo gloss paper and Ilford photo paper. Plastics films that can be printed using the inks according to the invention are, for example, transparent or milky/opaque. Suitable plastics films are, for example, 3M transparency film. Glossy paper, e.g. Epson glossy paper, is preferred.
Textile fibre materials that come into consideration are especially nitrogen-containing or hydroxy-group-containing fibre materials, e.g. textile fibre materials of cellulose, silk, wool or synthetic polyamides.
Examples of aluminium foils are surface-treated foils, e.g. vinyl-coated aluminium foils.
The present invention accordingly also relates to a method of printing paper, textile fibre material, plastics films or aluminium foils, preferably paper, textile fibre materials and plastics films, especially paper, in accordance with the ink-jet printing method, which comprises using an ink, preferably an aqueous ink, comprising a dye of formula (1), wherein X, R, m and n have the definitions and preferred meanings given for formula (1).
In ink-jet printing, individual droplets of the ink are sprayed onto a substrate in a controlled manner from a nozzle. For this purpose, predominantly the continuous ink-jet method and the drop-on-demand method are used. In the continuous ink-jet method, the droplets are produced continuously and any droplets not required for the printing are conveyed to a collecting vessel and recycled, whereas in the drop-on-demand method droplets are produced and printed as required; that is to say droplets are produced only when required for the printing. The production of the droplets can be effected, for example, by means of a piezo-ink-jet head or by means of thermal energy (bubble jet). For the process according to the invention, printing by means of an piezo-ink-jet head is preferred. Also preferred for the process according to the invention is printing in accordance with the continuous ink-jet method.
The recordings, for example prints, obtained are distinguished especially by good lightfastness properties and a high colour brilliance.
The present invention relates also to dyes of formula (1a) 
wherein
X, R, m and n have the definitions and preferred meanings given for formula (1), and dyes of formula (1b) 
wherein
X is hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl or a radical xe2x80x94CH2-CH2xe2x80x94Z, wherein Z is C1-C24alkoxy unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen; phenoxy unsubstituted or substituted in the phenyl ring; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety; phenylthio unsubstituted or substituted in the phenyl ring; amino; N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C10-C20terpeneamino; C5-C7cycloalkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom; or X has the same definitions as Z;
R is C1-C4alkyl, C1-C4alkoxy or halogen; and
m and n are each independently of the other the number 0, 1 or 2.
In respect of X, R, m and n in the dyes of formula (1b), the definitions and preferred meanings indicated under formula (1) apply in a corresponding manner.
The present invention relates also to a process for the preparation of dyes of formula (1a) or (1b), in which process
a compound of formula (3) 
is diazotised, the resulting diazo compound is coupled to the compound of formula (4) 
and the resulting azo dye is copper-treated with copper-yielding agents, R2being hydrogen or C1-C4alkyl, especially hydrogen or methyl, and in respect of R, X, m and n the definitions and preferred meanings indicated under formula (1a) or (1b) applying; or, preferably, a compound of formula (3) wherein X is vinyl or xe2x80x94CH2xe2x80x94CH2xe2x80x94Z and Z is a group removable under alkaline conditions, especially xe2x80x94OSO3H, is diazotised, the resulting diazo compound is coupled to the compound of formula (4), the resulting azo dye is copper-treated with copper-yielding agents and the resulting copper complex azo dye is reacted as appropriate with at least an equimolar amount of a compound of formula (5)
Zxe2x80x94Hxe2x80x83xe2x80x83(5)
Z having the definitions and preferred meanings given above with the exception of a group removable under alkaline conditions.
The compounds of formulae (3), (4) and (5) are known or can be prepared in accordance with processes known per se.
For example, the compound of formula (3) wherein X is xe2x80x94CH2xe2x80x94CH2xe2x80x94Z and Z has the definitions and preferred meanings given above with the exception of a group removable under alkaline conditions can be prepared, for example, from the corresponding precursor of the compound of formula (3) wherein X is vinyl or xe2x80x94CH2xe2x80x94CH2xe2x80x94Z and Z is a group removable under alkaline conditions, especially xe2x80x94OSO3H, by reaction with at least an equimolar amount of a compound of formula (5), for example under the conditions described below.
The diazotisation of the amine of formula (3) is effected in a manner known per se, for example with a nitrite, e.g. with an alkali metal nitrite, such as sodium nitrite, in a mineral-acid-containing medium, e.g. in a hydrochloric-acid-containing medium, at temperatures of, for example, from xe2x80x945 to 40xc2x0 C. and preferably at from 0 to 20xc2x0 C.
The coupling to the coupling component of formula (4) is effected in a manner known per se, at acidic, neutral to weakly alkaline pH values, for example at a pH value of from 0 to 8, and temperatures of, for example, from xe2x88x925 to 40xc2x0 C., preferably from 0 to 30xc2x0 C.
As copper-yielding agent there may be used salts that contain the copper as cation, e.g. copper sulfate, copper chloride or copper acetate. In some cases it will be advantageous to use complex copper compounds, for example in the form of copper-amine complexes, such as copper tetraaminesulfates of copper sulfate and ammonia, pyridine or monoethanolamine, or in the form of compounds that contain the copper bound in complex form, for example complex copper compounds of alkali metal salts of aliphatic aminocarboxylic acids or hydroxycarboxylic acids, such as of glycine, lactic acid and especially tartaric acid, such as sodium copper tartrate.
The treatment with the copper-yielding agent is carried out in a manner known per se, for example in an aqueous or organic-aqueous medium, for example at room temperature when readily metallizable starting compounds are present, or, when it is necessary for de-alkylation to take place at the same time as the metallization, by heating to temperatures of from 50 to 120xc2x0 C. in an open vessel, e.g. with reflux cooling or as appropriate in a closed vessel under pressure, the pH conditions being determined by the nature of the metallization method selected; for example, acidic copper-treatment with copper sulfate, especially in the presence of an alkali metal acetate, e.g. sodium acetate, or alkaline copper-treatment with copper tetraaminesulfate.
It is advantageous to use an excess of the compound of formula (5), for example a molar excess of from 1.2 to 20, preferably from 1.5 to 10.
The reaction with the compound of formula (5) is advantageously carried out in the presence of a base, e.g. an alkali metal hydroxide, an alkali metal alcoholate or benzyltrimethylammonium hydroxide, preferably an alkali metal hydroxide, e.g. sodium hydroxide or potassium hydroxide, or an acid, e.g. sulfuric acid, glacial acetic acid or boron trifluoride, preferably a base.
Ammonia and aliphatic amines are sufficiently basic to be added under mild conditions, in some cases also without the presence of a base or acid. In the case of aromatic amines, however, relatively high temperatures, for example temperatures above 100xc2x0 C., must be employed. The reaction conditions are governed especially by the nucleophilicity of the compound of formula (5). The reaction is advantageously carried out at temperatures of from 10 to 120xc2x0 C., preferably from 15 to 100xc2x0 C. and especially from 20 to 75xc2x0 C. These dependencies are generally known and are adequately described in the literature.
The sulfo groups in the dyes according to the invention are either in the form of the free sulfonic acid or, preferably, in the form of a salt thereof, e.g. in the form of a sodium, lithium, potassium or ammonium salt or in the form of a salt of an organic amine, e.g. in the form of a triethanolammonium salt or in the form of a salt of an amine Zxe2x80x94H of formula (5), wherein Z is N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, or uninterrupted or interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C10-C20terpeneamino; C5-C7cycloalkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; or piperazin-1-yl or piperidin-1-yl unsubstituted or substituted at the nitrogen atom, that is suitable for the preparation of the dyes according to the invention, the definitions and preferred meanings given above for the amine radical Z applying in corresponding manner. Special mention should be made of the salts of an amine of formula 
wherein the sum of the carbon atoms Ra+Rb+Rc is from 11 to 14 (e.g. (copyright)Primene 81 R, Rohm and Haas), which are suitable especially for the printing of aluminium sheets or foils.
The present invention accordingly relates also to the dyes of formula (1) wherein X is hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl, vinyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z is a group removable under alkaline conditions or is C1-C24alkoxy unsubstituted or substituted in the alkyl moiety, which may further be interrupted in alkyl moiety by oxygen; phenoxy unsubstituted or substituted in the phenyl ring; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety; phenylthio unsubstituted or substituted in the phenyl ring; amino; N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C10-C20terpeneamino; C5-C7cycloalkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom;
or X has the same definitions as Z with the exception of a group removable under alkaline conditions;
R is C1-C4alkyl, C1-C4alkoxy or halogen; and
m and n are each independently of the other the number 0, 1 or 2; in the form of a salt of an amine of formula 
wherein the sum of the carbon atoms Ra+Rb+Rc is from 11 to 14.
In respect of X, R, m and n, the definitions and preferred meanings indicated above under formula (1) apply.
The dyes according to the invention are also suitable for the dyeing and printing of hydroxy-group-containing and nitrogen-containing fibre materials, paper and aluminium sheets or aluminium foils in accordance with methods known per se, for example immersion processes, roller printing or film printing. The dyes according to the invention are also suitable for the dyeing or mordanting of wood.
Examples of fibre materials are silk, wool, synthetic polyamide fibres and polyurethanes and also cellulosic fibre materials of all kinds. Cellulosic fibre materials are, for example, the natural cellulosic fibres, such as cotton, linen and hemp, as well as cellulose and regenerated cellulose. The dyes according to the invention are also suitable for the dyeing or printing of hydroxy-group-containing fibres that are present in blend fabrics, for example mixtures of cotton with polyester fibres or polyamide fibres. The above-mentioned textile material can be in a wide variety of processing forms, e.g. in the form of fibres, yams, woven fabrics or knitted fabrics.
Examples of aluminium sheets or foils are surface-treated sheets or foils, e.g. vinyl-coated aluminium sheets or foils.
The present invention accordingly also relates to the use of the dyes according to the invention in the dyeing or printing of textile fibre materials, especially hydroxy-group-containing or nitrogen-containing fibre materials, wood, paper, aluminium sheets or aluminium foils.
The dyes according to the invention can be used for dyeing or printing in the generally customary, optionally preformulated form, for example in the form of aqueous dye solutions for the exhaust process or in the form of print pastes for use in screen printing.
The dyeings and prints obtained have good all-round properties, especially good fastness to light and a high colour brilliance. Dyeings and prints on hydroxy-group-containing or nitrogen-containing fibre materials are also distinguished by good fastness to rubbing, to wetting and to wet rubbing.
The present invention relates also to dye mixtures comprising a dye of formula (1) wherein X is hydroxy, unsubstituted or hydroxy-substituted C1-C4alkyl, vinyl or a radical xe2x80x94CH2xe2x80x94CH2xe2x80x94Z, wherein Z is a group removable under alkaline conditions or is C1-C24alkoxy unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen; phenoxy unsubstituted or substituted in the phenyl ring; C1-C4alkylthio unsubstituted or substituted in the alkyl moiety; phenylthio unsubstituted or substituted in the phenyl ring; amino; N-mono- or N,N-di-C1-C24alkylamino unsubstituted or substituted in the alkyl moiety, which may further be interrupted in the alkyl moiety by oxygen or by a radical xe2x80x94NR1xe2x80x94 in which R1 is hydrogen or unsubstituted or further substituted C1-C4alkyl; C10-C20terpeneamino; C5-C7cycloalkylamino unsubstituted or substituted in the cycloalkyl ring; phenyl- or naphthyl-amino or Nxe2x80x94C1-C4alkyl-N-phenyl- or Nxe2x80x94C1-C4alkyl-N-naphthyl-amino unsubstituted or substituted in the aryl moiety; morpholino; piperidin-1-yl; or piperazin-1-yl unsubstituted or substituted at the nitrogen atom; or X has the same definitions as Z with the exception of a group removable under alkaline conditions;
R is C1-C4alkyl, C1-C4alkoxy or halogen; and
m and n are each independently of the other the number 0, 1 or 2;
together with at least one dye from the group:
xanthene dyes of formula (6) 
xe2x80x83wherein
D1 are D2 are each independently of the other the radical of a diazo component of the benzene or naphthalene series,
R3, R4, R5 are R6 are each independently of the others C1-C4alkyl or unsubstituted or substituted C5-C7cycloalkyl, preferably C1-C4alkyl,
R7 are R8 are each independently of the other sulfo or carboxy, and
R9 is hydrogen or an acyl radical, preferably an acyl radical.
The numbering on the naphthalene coupling component of the dye of formula (7) indicates the possible bonding positions of the sulfo group.
Suitable radicals of a diazo component of the benzene or naphthalene series for D1 and D2 are described, for example, in U.S. Pat. No. 5,750,662 (columns 2 to 6). Xxe2x80x2 in the triazinyl radical of formula (5) in column 3 of U.S. Pat. No. 5,750,662 can also be a non-reactive substituent and may have, for example, the meanings indicated in the said patent specification for V as non-reactive substituents.
There come into consideration as C1-C4alkyl for R3, R4, R5 and R6 each independently of the others, for example, methyl, ethyl, n- or iso-propyl and n- or iso-butyl, preferably methyl and ethyl and especially ethyl.
There comes into consideration as C5-C7cycloalkyl for R3, R4, R5 are R6 each independently of the others especially the cyclohexyl radical. The mentioned cycloalkyl radicals may be unsubstituted or, for example, substituted by C1-C4alkyl, especially by methyl.
Examples of acyl radicals for R9 that come into consideration are C1-C4alkanoyl unsubstituted or substituted, for example by C1-C4alkoxy, halogen, hydroxy or by carboxy; benzoyl unsubstituted or substituted, for example by C1-C4alkyl, C1-C4alkoxy, halogen, hydroxy, sulfo or by carboxy; a triazinyl radical or a pyrimidyl radical. Suitable triazinyl radicals correspond, for example, to the radical of formula (5) in column 3 of U.S. Pat. No. 5,750,662, wherein Xxe2x80x2 nay also be a non-reactive substituent and may have, for example, the meanings given in the said patent specification for V as non-reactive substituents. Suitable pyrimidyl radicals correspond, for example, to the radical of formula (6) in column 3 of U.S. Pat. No. 5,750,662. R9 is preferably a triazinyl radical or a pyrimidyl radical.
Azo dyes of formula (7) also include dyes wherein two azo chromophores are bonded to one another by way of R9 as a triazinyl or pyrimidyl radical, preferably a triazinyl radical, by a bridge member, e.g. a 1,2-diaminopropyl, 1,4-phenylenediamino or 2,2xe2x80x2-disulfo-4,4xe2x80x2-diaminostilbene radical. Further suitable bridge members are described, for example, in U.S. Pat. No. 5,717,078 (columns 2 are 3).
The dyes of formulae (6), (7) and (8) are known or can be prepared in accordance with processes known per se.
The dyes of formulae (6), (7) and (8) are preferably red dyes.
Suitable dyes of formula (8) are disclosed, for example, in WO-A-99 29782, WO-A-99 31182, WO-A-96 24636 are EP-A-0 922 735.
Suitable xanthene dyes of formula (6) are, for example, the dyes of formulae (6a), (6b) and (6c) 
Suitable azo dyes of formula (8) are, for example, the dyes of formulae (8a), (8b) and (8c) 
The dye of formula (1) is present in the dye mixture according to the invention, for example, in an amount of from 2 to 98% by weight, preferably from 5 to 95% by weight and especially from 10 to 90% by weight, based on the total weight of the dyes in the mixture.
The dye mixtures according to the invention can be prepared, for example, by mixing the individual dyes together. The mixing process is carried out, for example, in suitable mills, e.g. ball mills or pinned disk mills, as well as in kneaders or mixers.
The dye mixtures are suitable especially for the preparation of inks, for example aqueous inks having the compositions given above, which are used especially in recording systems, e.g. in ink-jet printers.
The dye mixtures according to the invention can therefore also be obtained directly in the form of an aqueous ink formulation by dissolving the individual dyes together in water, together with the remaining constituents, or they can be prepared by mixing together inks that already comprise the appropriate individual dyes.
The recordings, for example prints, obtained are distinguished especially by good light fastness properties and a high colour brilliance.